I read on some thread here recently that some of the big commercial incubators have dedicated cooling fans because the eggs generate so much heat in the late stages of development. 10 thousand little hot rocks! Makes sense, bigger chicks, bigger metabolisms burning away as they finish developing.You're not crazy! My temps seem to climb on their own around the last week too. It's so frustrating but at the same time, I look at it as healthy babies growing in there![]()